Field of the Invention
The invention relates to a liquid crystal display material and an application thereof, and more particularly, to a photosensitive resin composition having good reliability under the conditions of high temperature and high humidity, and to a black matrix, a color filter, and a liquid crystal display device formed by using the composition.
Description of Related Art
In recent years, a variety of liquid crystal display techniques have been developed, and in order to improve the contrast and display quality of the current liquid crystal display device, a black matrix is usually disposed in the gap of the stripes and the dots of the color filter in the display device. The black matrix can prevent issues such as a decrease in contrast and color purity caused by light leakage between pixels. The material used in the conventional black matrix is mainly an evaporated film containing, for instance, chromium or chromium oxide. However, when the evaporated film is used as the material of the black matrix, disadvantages such as complicated process and costly materials exist. To solve these problems, a technique of forming the black matrix by a method of using a photosensitive resin composition through photolithography has previously been proposed.
Currently, the demand for the shading of the black matrix from the industry is increasing, and one solution is to increase the content of the black pigment, thereby improving the shading of the black matrix. For instance, JP 2006-259716 discloses a photosensitive resin composition for a black matrix. The photosensitive resin composition includes a high content of a black pigment, an alkali-soluble resin, a photopolymerization initiator, a reactive monomer having two functional groups, and an organic solvent. In particular, the reactive monomer having two functional groups can improve the reaction between compounds to form a pattern with high fineness. Therefore, in the photosensitive resin composition, when improving the shading by a method of increasing the content of the black pigment, the sensitivity of the photosensitive resin composition can still be maintained.
Further, JP 2008-268854 discloses a photosensitive resin composition for a black matrix. The photosensitive resin composition includes an alkali-soluble resin having a carboxylic acid group and an unsaturated group, a photopolymerized monomer having an ethylenically unsaturated group, a photopolymerization initiator, and a high content of black pigment. The photosensitive resin composition for a black matrix improves the resolution of the photosensitive resin composition having a high content of black pigment by using a specific alkali-soluble resin.
Although the current photosensitive resin composition having increased content of black pigment can increase shading, etc., the photosensitive resin composition of each prior art above readily generates issues such as poor reliability in an environment of high temperature and high humidity after lithography. Therefore, the development of a photosensitive resin composition for a black matrix having good reliability under the conditions of high temperature and high humidity is still required.